Heating/plumbing problems - airlock??

C

Caveat

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Hi

Well, put on the heating last night for the first time since we got our kitchen installed (for which water would have been turned off) and there is a problem.

Lots of hissing, creaking and clanging from the roofspace and one of the rads went crazy banging and rattling.

OK, I thought, airlock probably and went around bleeding the rads - true enough 3 or 4 released a fair bit of air before they "bubbled" but at least 3 not only didn't release air but water failed to surface at all even after 2 or 3 minutes.

What's going on - is this a simple airlock? If so what do I do next - if not not, what?

Thanks
 
Have you a pressurised system or small tank in attic?

You may need to top up system with water if pressurised or check water level in small tank to ensure it is refilling.
 
Thanks again Davy - no, not pressurised - tank in attic.

Why wouldn't the water in the tank be refilling though? It's only been installed a couple of months.

Am I barking up the wrong tree completely with the airlock idea?
 
I would say there is air in the system alright, but only because there is a lack of water.

Check to see if there is water in the small tank, the ballcock may be stuck.

If there is water in the tank, run the system and turn off any rads that heat. this will push airlocks out of lines.

If the pump is making winding noises, stop it as it is running dry, this will cause the pump to burn out.
 
Thanks very much Davy - will give it a go.

Could simply having the water turned off for a couple of days have caused this though? Because as I said, the tank/ballcock etc is almost brand new.
 
We said you got a new kitchen put in.
Did you get new rads put in?
Did you move the sink or get new applicances fitted to the hotwater system?
Is it a gas boiler in your kitchen or is there isolation valves for the rads in the kitchen?
The rads that you were not able to unairlock where are they situated in the house, are they in an extension or on the ground floor?
When you had the heating on did it heat up the water in the taps?

If you did get work done to the hotwater system, they would have turned off some of the valves in the hotpress and may not have turned them back on (the human element comes into play and people forget) this could be a simple reason why rads are isolated.

The clanging in the roof space did you go into the attic and see if the water was coming up the over flow pipe and back into the tank... that could be an indication the heating coil in the hot water tank are turned off
 
bob said:
We said you got a new kitchen put in.
Did you get new rads put in?
Click to expand...

No

Did you move the sink or get new applicances fitted to the hotwater system?
Click to expand...

No. Well, sink moved about 10 inches maybe if this counts.

Is it a gas boiler in your kitchen or is there isolation valves for the rads in the kitchen?
Click to expand...

No to both - OFCH - boiler outside.

The rads that you were not able to unairlock where are they situated in the house, are they in an extension or on the ground floor?
Click to expand...

No - bungalow - we have neither an extenstion nor another floor.

When you had the heating on did it heat up the water in the taps?
Click to expand...

Yes.


Well, no work done to hotwater system so I guess valves would not need to have been touched?

The clanging in the roof space did you go into the attic and see if the water was coming up the over flow pipe and back into the tank... that could be an indication the heating coil in the hot water tank are turned off.
Click to expand...

No, didn't look into the attic at all.

So based on those answers bob, any input/suggestions?
 
If your sink was moved then the hot water pipes in the hotpress must of been turned off. Turning off the mains will not isolate the hotwater.

The other obvious question to ask is ... Are both valves on the rads not heating turned on... the inflow and the outflow?
 
bob said:
If your sink was moved then the hot water pipes in the hotpress must of been turned off. Turning off the mains will not isolate the hotwater.
Click to expand...

OK - so this might be the problem - will talk to the kitchen fitter. Are you saying he absolutely must have turned off these valves and if indeed they were not turned back on, would we still get hot water in taps - because we are getting this?

The other obvious question to ask is ... Are both valves on the rads not heating turned on... the inflow and the outflow?
Click to expand...

Well I assume so - we didn't touch anything and I guess the fitter wouldn't have needed to? Everything was working previously.

Thanks for input.
 
Your first port of call has to be to check if there is water in the small tank.

Your kitchen guy may have turned off mains to stop both cold and hot, it would mean the large tank being emptied, unlikely but possible.

If you are getting hot water at taps now, then valves are open. If you are getting hot water after heating is on, this means flow and return to cylinder is on.

Check in your hot press, see the bottom pipe that enters the cylinder, this pipe is one of a pair the other pipe is directly above it about 18" apart. From this bottom pipe, you may have a half inch pipe leading to cylinder, if there is a red wheeled gate valve on this line, ensure it is open.
There should also be a gate vavle on that bigger bottom pipe, ensure it is not off also, half open is good. (it's a balancing valve.)

In my experiance, guys that aren't plumbers will generelly turn off every valve they see in a hot press and maybe forget to turn them on again.
 
OK Davy - thanks again.

Maybe a silly question, but if the tank is low on water and all the valves are then opened (assuming they are not, yet) will the tank then simply refill - assuming also there aren't any problems with the ballcock etc - or is there anything else we need to do?
 
DAvyJones is correct start in the attic and check the tanks.

You said that last night was the first time you had the heating on so are you sure the hot water from the taps was heated from the central heating. Normally in the evenings do you have hot water in the taps with out the heating on.... did you still have the immersion switch set to heating the water yesterday?... if so that could be the reason the water is hot so don't persume that the valves are open.

As DavyJones said its amazing what valves get turned off when someone is not sure what they are doing.
 
No, immersion wasn't on and water from taps was piping hot when the heat was on. We have a dual (back boiler + OFCH) system - fire was lit and OF was on whilst waiting for fire to get going, then OF turned off and pump turned on after about an hour.

Thanks guys - I'll see what tonight brings.
 
 
Back again

Your kitchen guy may have turned off mains to stop both cold and hot, it would mean the large tank being emptied, unlikely but possible.
Click to expand...

OK, have now found out that yes, the fitter did turn off the water at the mains.

So is it likely then that this be the source of my problems and if so, what do I need to do and in what order?
 
Check the ballcock of the small tank isn't stuck. you will have to take a trip in your attic.
 
OK checked both tanks - they look fine to me , about 3/4 full.

In my hotpress I see 4 'adjustables'

Red wheel at the bottom - which was open, 2 red 'levers' along vertical pipes which were open, and a green wheel near the ceiling - now this was closed.

Spoke to my fitter who says he closed this to do the work but thought he opened it afterwards - but obviously didn't.

As you probably know, haven't a clue what this green wheel is but on the assumption that it should be open, I've just opened it and turned on the OFCH.

Fingers crossed.

 
...and now uncrossed.

Problem solved. Thanks guys.

As it happens, didn't see anything that appeared to be a balancing valve - what would this look like?
 
Thats great news.






The red wheeled valve on the bottom pipe is what you are looking for.

You will have a dual coiled cylinder, one coil for back boiler, that has two one inch pipes entering parallel, there should be no valves on either of these pipes.

The other side should be as picture, two 3/4 inch entering cylinder, look for valve on bottom pipe.
 
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